FIG. 6 is a front view for showing the conventional structure of a lead frame and FIG. 7 is a side view of FIG. 6. There, a lead frame (101), a chip (103), and a mold (105) encasing part of the lead frame (101) and the chip (103), are shown.
With respect to the lead frame (101), a leg part (101a) extends at one side of the mold (105) for installing the same to a printed circuit board (not shown), and a radiation plate (101b) is provided at the other side of the mold in order to radiate the heat from the chip (103) to the outside.
Further, the center part of the radiation plate (101i) is provided with a hole (101c) for connecting to an external radiator (not shown).
In the power package lead frame constructed as above, the thickness (t) of the leg part(101a) and the thickness (T) of the radiation plate (101b) are made with different thickness at the time of manufacturing of the lead frame in order to maximize the radiation effect of the radiation plate (101b). The thickness (T) of the radiation plate (101b) is made thicker than the thickness (t) of the leg (101a). In order to maximize the radiation effect for radiating the heat generated from the chip to the outside, a conventional lead frame was made by using expensive lead frames of different thickness, which was problematic in terms of an increase in manufacturing costs.